Top-level crews spend days, even weeks, testing different sail-trim combinations. Experiment with all of your adjustments: boom vang, outhaul, halyard, sheets, even your steering. Make one adjustment at a time, and see if it improves boat speed. Observe your performance by watching your speedometer or GPS or by comparing your boat's speed against that of other boats. When you notice an improvement, make a note of the adjustment you made to create it. So you can reproduce the settings, mark the halyards and sheets, and mark the deck at the optimum settings for your jib-sheet leads and the mainsheet traveler.